Pollutant
A substance present in nature, in greater than natural abundance due to human activity, which ultimately has a detrimental effect on the environment and therefrom on living organisms and mankind.
Ex:
Lead, Mercury, Sulphur-dioxide, Carbon-dioxide etc…..
Contaminant
Any potentially undesirable substance (physical, chemical or biological).
It usually refers to the introduction of harmful human-made substances. However, some substances that may have harmful effects at high levels, like cadmium, occur naturally in ecosystems and may also be introduced through human activities.
Contaminants can be man-made substances produced by factories, such as DDT..It is the substance's long life and its ability to spread over a wide area that makes an industrial contaminant such a problem.
When Environmental Pollution takes place?
When the environment cannot process and neutralize harmful by-products of human activities (for example, poisonous gas emissions) in due course without any structural or functional damage to its system.
A pollutant is a waste material that pollutes air, water or soil. Three factors determine the severity of a pollutant:
Chemical nature
Concentration
Persistence
Sources of Environmental Pollution
Fossil Fuels
Oil. Gas. Coal
Products as all sorts of plastics.
Solvents. Detergents.
A wide range of chemicals for industrial use
Common sources of fossil fuel pollution:
Industry:
Power-generating plants
Petroleum refineries
Petrochemical plants
Production and distribution of fossil fuels
Other manufacturing facilities
Transport:
Road transport (motor vehicles)
Shipping industry
Aircraft
Combustion. Construction. Mining. Agriculture. Warfare.
Non-Fossil Fuel Sources
Agriculture and Livestock Farming - Largest generator of ammonia emissions resulting in air pollution.
Chemicals such as pesticides and fertilizers are also widely used in agriculture, which may lead water pollution and soil contamination as well.
Trading activities may be another source of pollution.
Packaging of products sold in supermarkets and other retail outlets, Residential sector and Medical Wastes generates large quantities of solid waste that ends up either in landfills or municipal incinerators leading to soil contamination and air pollution.
Environmental Pollution
Physical
Chemical
Biological
As soon as a pollutant enters environment, agencies of transfer, transport start acting on it almost simultaneously.
While the pollutant is dispersed in the medium and diluted, it also undergoes abiotic transformation in which solar radiations; water and air play an important part.
The pollutant may thus be broken down or altered in the abiotic environment itself.
Abiotic transformation of pollutants is the only process available in the atmosphere
as it lacks the biotic agencies which occur on land as well as in water.
Abiotic and Biotic transformation may alter or degrade the pollutant molecules. How?
Photolysis: absorption of solar radiations - pollutant molecules in the environment react photo-chemically and acquire an excited state – change in molecular structure
Hydrolysis: Hydrolytic dissociation of pollutants is a process which is of greater importance on land and in water
Biotic Transformation of Pollutants
Microbial and Plant activity – In Soil and Water
End Product - Formation of Hydrocarbons (e.g. methane CH4, alkanes, alkenes, aromatics), ammonia (NH3), hydrogen sulfide (H2S) and R-S, reduced metal oxides (Fe2+, Mn2+).
Chemical Processes Involved –
Oxidation
Reduction
Hydrolysis
Elimination
Substitution
Photolysis
From where we can get the samples for Pilot Study for the Transformations?
Waste Disposal Sites
Sewage Channels before mixing to the main drainage channels
Ambient air from Industrial, Mining, Agricultural Areas
River Channels within Agricultural fields
A substance present in nature, in greater than natural abundance due to human activity, which ultimately has a detrimental effect on the environment and therefrom on living organisms and mankind.
Ex:
Lead, Mercury, Sulphur-dioxide, Carbon-dioxide etc…..
Contaminant
Any potentially undesirable substance (physical, chemical or biological).
It usually refers to the introduction of harmful human-made substances. However, some substances that may have harmful effects at high levels, like cadmium, occur naturally in ecosystems and may also be introduced through human activities.
Contaminants can be man-made substances produced by factories, such as DDT..It is the substance's long life and its ability to spread over a wide area that makes an industrial contaminant such a problem.
When Environmental Pollution takes place?
When the environment cannot process and neutralize harmful by-products of human activities (for example, poisonous gas emissions) in due course without any structural or functional damage to its system.
A pollutant is a waste material that pollutes air, water or soil. Three factors determine the severity of a pollutant:
Chemical nature
Concentration
Persistence
Sources of Environmental Pollution
Fossil Fuels
Oil. Gas. Coal
Products as all sorts of plastics.
Solvents. Detergents.
A wide range of chemicals for industrial use
Common sources of fossil fuel pollution:
Industry:
Power-generating plants
Petroleum refineries
Petrochemical plants
Production and distribution of fossil fuels
Other manufacturing facilities
Transport:
Road transport (motor vehicles)
Shipping industry
Aircraft
Combustion. Construction. Mining. Agriculture. Warfare.
Non-Fossil Fuel Sources
Agriculture and Livestock Farming - Largest generator of ammonia emissions resulting in air pollution.
Chemicals such as pesticides and fertilizers are also widely used in agriculture, which may lead water pollution and soil contamination as well.
Trading activities may be another source of pollution.
Packaging of products sold in supermarkets and other retail outlets, Residential sector and Medical Wastes generates large quantities of solid waste that ends up either in landfills or municipal incinerators leading to soil contamination and air pollution.
Environmental Pollution
Physical
Chemical
Biological
As soon as a pollutant enters environment, agencies of transfer, transport start acting on it almost simultaneously.
While the pollutant is dispersed in the medium and diluted, it also undergoes abiotic transformation in which solar radiations; water and air play an important part.
The pollutant may thus be broken down or altered in the abiotic environment itself.
Abiotic transformation of pollutants is the only process available in the atmosphere
as it lacks the biotic agencies which occur on land as well as in water.
Abiotic and Biotic transformation may alter or degrade the pollutant molecules. How?
Photolysis: absorption of solar radiations - pollutant molecules in the environment react photo-chemically and acquire an excited state – change in molecular structure
Hydrolysis: Hydrolytic dissociation of pollutants is a process which is of greater importance on land and in water
Biotic Transformation of Pollutants
Microbial and Plant activity – In Soil and Water
End Product - Formation of Hydrocarbons (e.g. methane CH4, alkanes, alkenes, aromatics), ammonia (NH3), hydrogen sulfide (H2S) and R-S, reduced metal oxides (Fe2+, Mn2+).
Chemical Processes Involved –
Oxidation
Reduction
Hydrolysis
Elimination
Substitution
Photolysis
From where we can get the samples for Pilot Study for the Transformations?
Waste Disposal Sites
Sewage Channels before mixing to the main drainage channels
Ambient air from Industrial, Mining, Agricultural Areas
River Channels within Agricultural fields
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